Apparatus for treating board



y 7, 1963 T. D. BISHOP 3,381,563

APPARATUS FOR TREATING BOARD Filed Jan. 20, 1966 United States Patent 3,381,563 APPARATUS FOR TREATING BOARD Thomas Desmond Bishop, Solihull, England, assignor to The Deritend Engineering Company Limited, Birmingham, England, a British company Filed Jan. 20, 1966, Ser. No. 521,947 Claims priority, application Great Britain, Jan. 27, 1965, 3,497 65 1 Claim. (Cl. 83-303) ABSTRACT OF THE DISCLOSURE Background of the invention This invention relates to apparatus for treating board in the manufacture of articles of relatively complicated shape such as ji -saw puzzles.

A conventional jig-saw puzzle (of cardboard) is made from a board which is die cut in a single operation to produce the various interlocking portions. The die for this purpose hitherto has invariably been a flat platen bearing a pattern of cutting rules which have one uppermost sharpened edge and which are bent to the desired shapes, a first set of rules extending generally parallel in one direction and a second set being generally transverse to the first set and either being composed of short pieces so as to extend between the rules of the first set, or both sets being notched to intersect for the same effect. It is necessary to braze, weld or otherwise secure each junction of rule pieces and ensure that the cutting edges extend up to one another as closely as possible otherwise the individual jig-saw pieces will not readily sever after the board has been die cut. In use the die and board are placed together under pressure and the cut board is stripped from the die before the pieces of the jig-saw are separated.

It will be appreciated that the die is very expensive to produce, although it can be used to make a large number of jig-saws at a reasonable speed by reciprocating movement past an impression roll, or by reciprocating movement relative to a second platen.

Summary of the invention The object of the present invention is to provide apparatus which will reduce the cost of die production and substantially increase the production speed possible.

In accordance with the present invention apparatus for the treatment of board in the manufacture of articles comprises two roll pairs arranged to successively operate upon board fed through the nips therebetween, each pair of rolls being provided with one pattern of cutting rules, the rules on the second roll pair being transverse to those on the first roll pair, and the roll pairs being synchronised in operation.

The rules may be secured to the rolls by any convenient means for example they may be set in plastic sheets wrapped around the roll peripheries, carried on carrier straps clamped to the rolls or secured by welded studs,

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1 rules on each roll so that there is no necessity for combrackets or any other means. It will be appreciated that paratively complicated welding or the like thus substantially reducing the cost of die production.

Where jig-saw puzzles are to be manufactured it is essential that the rule patterns are located properly with respect to one another on the two rolls concerned and that synchronisation is maintained, so as to avoid the possibility of a production of non-interlocking pieces, fragments of boards and the like. It is always possible to setup the apparatus empirically and the cost of a few boards scrapped is usually immaterial in a long production run.

The continuous rotary operation of the roll pairs inherently enables a vastly increased production rate to be maintained, and moreover it may be possible to set up for jig-saw production using rules extending over substantially the whole of each rule carrying roll of each pair and produce a whole series of puzzles of different dimensions in which case different areas of the dies are in use and furthermore each successive puzzle may be slightly different to the last due to the use of a different portion of the peripheral extent of each roll. Where complete separate pictures are fed between the rolls the jigsaw puzzle may be produced without other cutting means, but in other cases the rolls may carry or be associated with trimming wheels or knives.

A preferred embodiment of the invention is now more particularly described with reference to the accompanying drawings wherein:

Brief 'description of the drawing FIGURE 1 is a diagrammatic elevation of a jig-saw puzzle making machine;

FIGURE 2 is a perspective view thereof and FIGURE 3 is a fragmentary plan of a portion of the cutting roll 10.

Description of the preferred embodiments The machine shown in FIGURE 1 comprises a first roll pair comprising an upper cutting roll 10 and a lower impression roll 11, and a second roll pair comprising an upper cutting roll 12 and a lower impression roll 13.

All of the rolls are geared together in synchronism.

The cutting roll 10 is provided with a pattern of cutting rule consisting of a plurality of separate pieces of such rule which extend substantially along the length of the roll, parallel to the roll axis. Each piece of rule comprises a plurality of straight portions 15 connected by arcuate extending portions 16 and 17 which are conveniently located on opposite sides of the straight portions. Each arcuate portion may extend around more than of the complete circle and each arc extends around a stud 18 which is generally cylindrical and which is welded to a sheet metal form 14 surrounding and secured to the roll. The studs and the technique of welding them to the form are more particularly described in co-pending application Ser. No. 520,691, filed Jan. 14, 1966.

By virtue of the arcuate portions 16, 17 extending more than half way around the perimeter of each stud, the rule is conveniently securely fixed to the plurality of studs in each roll thereof, merely as a push fit on to these studs. The studs are of less height than the rule so that the cutting edge of the rule is clear of the upper edge of each stud.

At each end of each rule there may be a straight portion 19 of greater length than the portions 15 and this may terminate at a further stud 20 to which the rule is positively fixed by a srcew 21. Thus each end of each rule is fixed by such a screw so that the rule is securely fastened to the form.

The width of board to be cut by the cutting roll 10 is less than the total width of the roll by an amount such that the lateral edge of the board extends across the straight portions 19 at each edge of the jig-saw panel.

The impression roll 11 is covered with a sheet metal layer but could be coated with a yielding substance such as polyurethane in which the cutting rule cuts so as to ensure complete severence along the lines of the rule.

The cutting roll 12 is generally similar to the cutting roll except that the rule length extends circumferentially about the roll. While it is possible to utilize rules extending around the entire circumference of the roll, it is often sufiicient to provide rules extending over a portion of the circumference only, the portion being slightly greater than the length of the boards fed through the roll pairs, and being timed relative to the rotation so that cutting takes place in a similar manner. It will be appreciated that in the case of rules on the roll 12, the rule will be curved along its length, and hence each two adjacent portions embracing studs will be at a slight angle to one another, since the studs lie on radii of the roll, and this makes captive screws and the like unnecessary. It will be appreciated that it is not essential to provide rules at completely regularly spaced intervals either along the roll axis or about the roll circumference, or to provide arcuate portions which extend on opposite sides of the straight portions alternatively, so that there is a 4t small difference between substantially any two pieces of the finished jigsaw.

I claim:

1. An apparatus for the treatment of board comprising two roll pairs arranged to operate successively upon board fed through the nips thereof, wherein the improvement comprises a form surrounding one roll of each pair and having studs welded thereto, and a series of cutting rules, each having arcuately extending portions which substantially embrace the studs and are separated by straight portions, the rules on the roll of the second pair being transverse to the rules on the roll of the first pair, and the roll pairs being synchronised in operation.

References Cited UNITED STATES PATENTS 505,189 9/1893 Climber 83-665 691,499 1/1902 Snedden 83302 1,618,191 2/1927 Hemberger 83698 X 2,170,166 8/1939 Sweet 76107 2,759,542 8/1956 Weisshuhn 83333 X 3,250,152 5/1966 Kirby et a1. 76107 3,302,490 2/1967 Bishop 76-l07 JAMES M. MEISTER, Primary Examiner. 

